ADR 0256: one reader of the drives, and a stuck read is said

After the second review: smartd is dropped as a second reader that could wake or keep awake the drives,
a stuck read or a drive not looked at is unhealthy, a drive asleep for a day is HIGH and never unhealthy,
and a board chip's maximum says nothing of a fan. The never-woken and hourly claims now say exactly what
holds.

03-DESIGN/01-to-be/48-a-module-says-how-it-is-healthy.md

@@ -284,24 +284,27 @@ health of this design, not yet through the machine's own judgement as §10 does
 ```
   sensors on one machine                                   node-engine            controller
   ┌──────────────────────────────────────────────┐
-  │ smartd (unit)       watches every drive,     │ unit ──► liveness + readiness
-  │                     never wakes one asleep   │
-  │ watch (root)        each drive's health      │
-  │                     (spinning: hourly); fans │ tool ──► asks sensors_health ──► module.sensors.<m>.unhealthy
-  │                     that ran since boot      │          every 60 s, 2 looks     (the why is its evidence)
-  │ tools (operator)    /sys and the watch's     │
-  │                     readings; read-only      │
+  │ drive reader (root) each drive's health,     │ unit ──► liveness + readiness
+  │                     never one asleep; each   │
+  │                     read bounded, or said    │
+  │ fan watch           fans that ran since boot │ tool ──► asks sensors_health ──► module.sensors.<m>.unhealthy
+  │                                              │          every 60 s, 2 looks     (the why is its evidence)
+  │ tools (operator)    /sys and the two files;  │
+  │                     read-only                │
   └──────────────────────────────────────────────┘
 ```
 
 - **Unhealthy means the hardware is failing, measured against its own thresholds:** a CPU, GPU, drive or
   zone temperature at or above its own critical value (a board chip's is shown, never judged); a drive that
   says it is failing (a SATA drive's verdict, a pre-failure attribute failing now, an NVMe critical warning
-  bit other than temperature); a fan that ran since boot and reads 0 while the CPU, the board or a sensor on
-  its own chip is at or above its own maximum; memory that reports an uncorrectable error; or the watch's
-  readings older than five minutes. HIGH readings and fan notes are said by the tools and raise nothing.
-- **A drive is never woken, and is read seldom enough to sleep:** a spinning drive hourly, by the watch and
-  by smartd, because a read can restart a standby timer the mesh cannot yet see.
+  bit other than temperature); a fan that ran since boot and reads 0 while a CPU sensor, a thermal zone or a
+  sensor on its own non-board chip is at or above its own maximum; memory that reports an uncorrectable
+  error. **Or that the module's own processes are stale:** a file five minutes old, a drive's read stuck
+  past its bound, a drive not looked at for twice its cadence. HIGH readings, fan notes and a drive asleep
+  for a day are said by the tools and raise nothing.
+- **One reader, never waking a drive that can say it sleeps:** the module's drive reader alone reads the
+  drives (no `smartd`), a spinning drive hourly, because a read can restart a standby timer the mesh cannot
+  yet see.
 - **A class the machine lacks is not present**, never a failure: a virtual machine with no sensor and no
   SMART drive is healthy.
 - **The cost of using module health for the machine's fault** is that the condition names the module, and a
@@ -320,7 +323,7 @@ health of this design, not yet through the machine's own judgement as §10 does
 | D — the proof | mesh-lab, mesh-catalog | the bed; the catalogue's check starting every changed resource on it; adopted image checks proved | the replay of the studio's false *unhealthy* fails the bed, not a machine |
 | E — the migration | mesh-catalog, mesh-controller | the declarations of §9 steps 2–5; the count kept in the catalogue and its test; `module check` refusing after the date | the count is zero, or the date has passed and `module check` refuses |
 | F — the machine's network | `mesh-host` (node-engine), `mesh-controller`, `mesh-catalog` | §10: the five parts judged on two looks and stated; the three conditions said once; the gate waiting on another's; `node show` | the tests of ADR 0241 pass; the drill's replay raises and clears; a VPN connect on the laptop is raised naming its writer and cleared by the reconcile |
-| G — the machine's hardware | `mesh-catalog` | §11: the `sensors` module, its tools, `smartd` and the watch, both checks declared | its tests pass; `module check` accepts its health; on the first machine both checks are stated healthy |
+| G — the machine's hardware | `mesh-catalog` | §11: the `sensors` module, its tools, the drive reader and the fan watch, both checks declared | its tests pass; `module check` accepts its health; on the first machine both checks are stated healthy |
 
 Phases A and B may be built together; A is live first, because it judges without a single declaration.